Experimental Study on Effect of Human-Load on Vertical Dynamic Characteristics of Wooden Floor (Part 1)

Abstract

ImpaGt hammer tests we τe conducted to demonstrate the effect of human load o 口 vertical vlbrational characteristics ( first natuml frequency and damping factOr )of wooden fioors ． The specimen was a 6 ． 5m − long − span and LOm − wide wooden Hoo π Gonsisted of two l20mm wide and 300mm deep laminated wood timbers md 21mm ・ thick plywood sub − fieor ． The support and live load oonditions ofthe spccimen were changed ． The live load comb ed wi 出 humm bad d iture lo 記 ged 丘om O to 60 kg！ m2 respe 。tively wer 即 plied to血c wooden Hoor The test results indicate ， i ) Human load hardly affectS the first natural 廿eruency of the wooden 且 oor ， ii ) The value of damping factor at first ． natural frequency increases in proportion to the rate of humm IQad over the weight of a wood ¢ n Hoor ， iii )The measured first na 血 ral fre 叩 en − cies ofthe wooden 們oors ◎ oinoide with those calculatod according to the vibration theory fbr bending Gontinuous model with the bending stiff − ness and the weight 仙 e sum of dead load and fUrnitUre load except the human ［ oad ) ofthe wooden 們oo 鵡 煙 y 汐 o 鳩

Development and Vibration Control of Frequency Adjustable Tuned Mass Damper Based on Magnetorheological Elastomer

“…On the other hand, the natural frequency of the main structure may vary at different stages. For example, the mass of the main structure changes during the construction process [ 12 ], the change of water level in an elevated storage tank, and the change of live load on a bridge will also change the natural frequency of the main structure [ 13 , 14 ]. Changes in structural natural frequency are not only affected by changes in mass, but also by degradation of structural stiffness.…”